Integrated circuit (IC) manufacturers are employing increasingly smaller dimensions and corresponding technologies to make smaller, high-speed semiconductor devices. Along with these advancements, the challenges of maintaining yield and throughput have also increased.
A semiconductor wafer typically includes dies (also referred to as chips) separated from each other by scribe lines. Individual chips within the wafer contain circuitry, and the dies are separated by sawing and then are individually packaged. Conventionally, the sawing is performed using mechanical force. This, however, incurs mechanical force on chips adjacent to the scribe lines, resulting in damage to the chips.
Recently, laser was used for the die sawing, in which a laser is projected on the scribe line, and hence the laser-projected portions are cut apart. Advantageously, the laser sawing does not apply mechanical force to the chips, and hence the mechanical force related damage is substantially eliminated. However, laser sawing is accompanied by a significant amount of heat, which may cause the local temperature of the portions of chips close to the scribe lines to be very high. The devices that are exposed to the high temperatures may be damaged, or having their performance shifted.
Conventionally, to solve the heat problem caused by the laser sawing, scribe lines were broadened so that the laser-passing path is farther away from the neighboring chips. For example, scribe lines may have to be expanded from 80 μm to about 300 μm in width. Such an increase in the scribe lines results in the reduction of the chip count in wafers.
Accordingly, what is needed in the art is a method and/or an integrated structure that may incorporate laser sawing thereof to take advantage of the benefits associated with the reduced mechanical force while at the same time overcoming the deficiencies of the prior art.